<!--
    /**
     * 树形下拉选择组件，下拉框展示树形结构，提供选择某节点功能，方便其他模块调用
     * 调用示例：
     * <tree-multi-select :height="400" // 下拉框中树形高度
     *              filter // 筛选树
     *              :width="200" // 下拉框中树形宽度
     *              size="small"  // 输入框的尺寸: medium/small/mini
     *              :data="data" // 树结构的数据
     *              :defaultProps="defaultProps" // 树结构的props
     *              multiple   // 多选
     *              checkStrictly // 多选时，严格遵循父子不互相关联
     *              :nodeKey="nodeKey"   // 绑定nodeKey，默认绑定'id'
     *              :checkedKeys="defaultCheckedKeys"  // 传递默认选中的节点key组成的数组
     *              @popoverHide="popoverHide"> // 事件有两个参数：第一个是所有选中的节点ID，第二个是所有选中的节点数据
     *              </tree-multi-select>
     */
-->
<template>
  <div>
    <div class="mask" v-show="isShowSelect" @click="isShowSelect = !isShowSelect"></div>
    <el-popover placement="bottom-start" :width="width" trigger="manual" v-model="isShowSelect" @hide="popoverHide()"
      @show="popoverShow()">
      <el-input v-if="filter" style="padding: 5px;margin: 5px 0;" size="small" placeholder="输入名称进行搜索"
        prefix-icon="el-icon-search" v-model="filterText">
      </el-input>
      <el-tree class="common-tree" :style="style" ref="tree" :data="data" :filter-node-method="filterNode"
        :props="defaultProps" :show-checkbox="multiple" :node-key="nodeKey" :check-strictly="checkStrictly"
        default-expand-all :expand-on-click-node="false" :highlight-current="true" @node-click="handleNodeClick"
        @check-change="handleCheckChange"></el-tree>
      <el-select :style="selectStyle" slot="reference" ref="select" :size="size" v-model="selectedData"
        :multiple="multiple" collapse-tags @click.native="isShowSelect = !isShowSelect" class="tree-select"
        :clearable="clearable" :placeholder="placeholder ? placeholder : '请选择'" @clear="clearKeys">
        <el-option v-for="item in options" :key="item.value" :label="item.label" :value="item.value"></el-option>
      </el-select>
    </el-popover>
  </div>
</template>

<script>
export default {
  name: 'TreeMultiSelect',
  props: {
    //如果子节点权限是否只获取父节点信息
    sonNodeCheckAllGetParentNode: {
      type: Boolean,
      default() {
        return false;
      }
    },
    dimKey: {
      type: String,
      default() {
        return '';
      }
    },
    placeholder: {//占位文字
      type: String,
      default() {
        return '';
      }
    },
    clearable: {//是否清空
      type: Boolean,
      default() {
        return false;
      }
    },
    // 树结构数据
    data: {
      type: Array,
      default() {
        return [];
      }
    },
    defaultProps: {
      type: Object,
      default() {
        return {};
      }
    },
    // 筛选树
    filter: {
      type: Boolean,
      default() {
        return false;
      }
    },
    selectWidth: {
      type: Number,
      default() {
        return 0;
      }
    },
    // 配置是否可多选
    multiple: {
      type: Boolean,
      default() {
        return false;
      }
    },
    nodeKey: {
      type: String,
      default() {
        return 'id';
      }
    },
    // 显示复选框情况下，是否严格遵循父子不互相关联
    checkStrictly: {
      type: Boolean,
      default() {
        return false;
      }
    },
    // 默认选中的节点key数组
    checkedKeys: {
      type: Array,
      default() {
        return [];
      }
    },
    size: {
      type: String,
      default() {
        return 'small';
      }
    },
    width: {
      type: Number,
      default() {
        return 250;
      }
    },
    height: {
      type: Number,
      default() {
        return 300;
      }
    }
  },
  data() {
    return {
      filterText: '',
      isShowSelect: false, // 是否显示树状选择器
      options: [],
      selectedData: [], // 选中的节点
      style: 'width:' + (this.width - 15) + 'px;' + 'height:' + this.height + 'px;',
      selectStyle: 'width:' + ((this.selectWidth > 0 ? this.selectWidth : this.width) + 24) + 'px;',
      checkedIds: [],
      checkedData: []
    };
  },
  mounted() {
    this.$nextTick(() => {
      this.initCheckedData();
    })
  },
  methods: {
    clearKeys() {
      this.selectedData = '';
      this.$refs.tree.setCurrentKey(null);
      this.checkedIds = this.$refs.tree.getCurrentKey();
      this.checkedData = this.$refs.tree.getCurrentNode();
      this.$emit('popoverHide', this.checkedIds, this.checkedData);
    },
    filterNode(value, data) {
      if (!value) return true;
      let oldStr = data.label.toLocaleUpperCase()
      let newStr = value.toLocaleUpperCase()
      return oldStr.indexOf(newStr) !== -1;
    },
    initCheckedData() {
      if (this.multiple) {
        if (this.checkedKeys.length > 0) {
          // 勾选上传进来的节点
          this.$refs.tree.setCheckedKeys(this.checkedKeys);
        } else {
          // 清空所有勾选
          var checkedKeys = this.$refs.tree.getCheckedKeys(); // 所有被选中的节点的 key 所组成的数组数据
          for (let i = 0; i < checkedKeys.length; i++) {
            this.$refs.tree.setChecked(checkedKeys[i], false);
          }
        }
        this.handleCheckChange();
      } else {
        if (this.checkedKeys.length > 0) {
          // 选中传进来的节点
          var item = this.checkedKeys[0];
          this.$refs.tree.setCurrentKey(item);
          var node = this.$refs.tree.getNode(item);
          node && (this.selectedData = node.label);
        } else {
          // 清空选中
          this.selectedData = '';
          this.$refs.tree.setCurrentKey(null);
        }
      }
    },
    popoverShow() {
      this.$emit('popoverShow');
    },
    getSimpleCheckedNodes(store) {
      const checkedNodes = [];
      const traverse = function (node) {
        const childNodes = node.root ? node.root.childNodes : node.childNodes;
        childNodes.forEach(child => {
          if (child.checked) {
            checkedNodes.push(child.data);
          }
          if (child.indeterminate) {
            traverse(child);
          }
        });
      };
      traverse(store)
      return checkedNodes;
    },
    popoverHide(fromChange) {
      if (this.multiple) {
        this.checkedIds = this.$refs.tree.getCheckedKeys(); // 所有被选中的节点的 key 所组成的数组数据
        this.checkedData = this.$refs.tree.getCheckedNodes(); // 所有被选中的节点所组成的数组数据
      } else {
        this.checkedIds = this.$refs.tree.getCurrentKey();
        this.checkedData = this.$refs.tree.getCurrentNode();
      }
      let checkedIds = this.checkedIds;
      let checkedData = this.checkedData;
      if (this.sonNodeCheckAllGetParentNode) {
        let res = this.getSimpleCheckedNodes(this.$refs.tree.store);
        checkedData = res;
        checkedIds = res.map(item => item[this.nodeKey]);
      }
      this.$emit('popoverHide', checkedIds, checkedData, fromChange);
    },
    // 节点被点击时的回调,返回被点击的节点数据
    handleNodeClick(data, node) {
      if (!this.multiple) {
        let tmpMap = {};
        tmpMap.value = node.key;
        tmpMap.label = node.label;
        this.options = [];
        this.options.push(tmpMap);
        this.selectedData = node.label;
        this.isShowSelect = !this.isShowSelect;
      }
    },
    // 节点选中状态发生变化时的回调
    handleCheckChange() {
      var checkedKeys = this.$refs.tree.getCheckedKeys(); // 所有被选中的节点的 key 所组成的数组数据
      this.options = checkedKeys.map(item => {
        var node = this.$refs.tree.getNode(item); // 所有被选中的节点对应的node
        let tmpMap = {};
        tmpMap.value = node.key;
        tmpMap.label = node.label;
        return tmpMap;
      });
      this.selectedData = this.options.map(item => {
        return item.label;
      });
      this.popoverHide(true)
    }
  },
  watch: {
    filterText(val) {
      this.$refs.tree.filter(val);
    },
    isShowSelect(val) {
      // 隐藏select自带的下拉框
      this.$refs.select.blur();
    },
    checkedKeys(val) {
      if (!val) return;
      if (!val.includes('null')) return;
      this.checkedKeys = val;
      this.initCheckedData();
    }
  }
};
</script>

<style scoped>
.mask {
  width: 100%;
  height: 100%;
  position: fixed;
  top: 0;
  left: 0;
  opacity: 0;
  z-index: 2000;
}

.common-tree {
  overflow: auto;
}
</style>

<style>
.tree-select .el-select__tags .el-tag .el-tag__close {
  display: none;
}

.tree-select .el-select__tags .el-tag .el-icon-close {
  display: none;
}

/*.el-scrollbar .el-scrollbar__wrap {*/
/*	overflow-x: hidden;*/
/*}*/
.el-tree>.el-tree-node {
  min-width: 100%;
  display: inline-block;
}
</style>
